“It has been decided to upgrade the existing travel warning vis-a-vis Turkey from a basic concrete threat to a high concrete threat, and to reiterate our recommendation to the public to avoid visiting the country and –- for Israelis currently in Turkey -– to leave as soon as possible,” a government statement said.

The statement said the bombing highlighted the threat from Islamic State group militants “against tourist targets throughout Turkey and proves high capabilities of carrying out further attacks”.

“Terrorist infrastructures in Turkey continue to advance additional attacks against tourist targets –- including Israeli tourists -– throughout the country,” it said.

Tens of thousands of Israelis visit nearbyTurkey each year despite strained diplomatic relations between the two countries.

Three Israelis and an Iranian were killed and 39 people wounded when a man blew himself up on Istiklal Caddesi, a famous shopping street in the heart of Turkey’s biggest city, on March 19.

The Turkish government said the bomber had links to IS.

IS has been blamed for four bombings that have rocked Turkey in the past eight months, including a massacre at a peace rally in the capital Ankara in October that claimed 103 lives.